An emergency response or disaster service vehicle owned or leased and operated by the American National Red Cross, or any chapter or branch thereof, and equipped and clearly marked as a Red Cross emergency service or disaster service vehicle, may display flashing amber warning lights to the front, sides, or rear of the vehicle while at the scene of an emergency or disaster operation. Vehicles not used on emergency response shall not be included.
Source:
Section 25259.5, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=VEH§ionNum=25259.5..